Bitcoin Forum

I need to use Bitcoins on the go so need Android support. I may also sometimes need to access the same coins from laptop. So here are my requirements for a wallet:

1. A single wallet that is constantly synced on android and two or three laptops I use (e.g. like Dropbox)
2. Quick start-up, and "catching up"
3. Web-wallets are ok (then 1. and 2. will be satisfied) as long as I don't have to trust the provider. Even if he wants to he cannot steal my bitcoins.
4. Resistant to attacks from ISPs etc with very high probability.
5. Resistant to attacks from stolen phone/hard drive. (need strong password protection on wallet.. something like Keepass with a key-file which is not stored on Dropbox)

What is the best wallet that comes close to achieving all 5.
(1, 2, 5 are absolutely essential)

Coinbase.com - Works on Android as well with Multi Factor Authentication
Blockchaininfo Wallet

Thanks, I will check out coinbase.com. However, from first look, it seems that coinbase keeps our private keys on the server. What I would like ideally is to keep the private key on a (possibly thin) client. Bitcoin spinner is one such client I could find.

However the main problem I am facing is to use the same private keys from my laptop and the phone. This seems to be an unsolved problem as of now.

I don't want to maintain two wallets (at least for the funds that I regularly use).

That's not explicitly supported because it's dangerous and easy to screw up. If your two wallets get out of sync you can create invalid double spends that may be hard to recover from.

If you're absolutely sure you want to do this, you can - the latest versions of the Android "Bitcoin Wallet" app from Andreas Schildbach allow import of private keys. So create some on your laptop (eg, with MultiBit), then import into the Android app, tell it to resync and you're done. But don't say we didn't warn you.

It's not at all unsolved. Blockchain.info uses the same wallet on all devices.

That's because it won't let you do anything if the central server goes down. Obviously if you're willing to have that constraint, it can be implemented with other wallet software too.

I use blockchain.info for small purchases due to the convenience of having my address book and keys synced between my phone, PC and laptop.

I also imported the private key for that wallet into Armory as a backup so that if something happens to the central server I won't be unable to access my balance.

I agree with the warning, especially with the addition that it is probably unwise to keep access to your whole wallet on a mobile device. Phones get stolen, other apps abuse their permissions, and there's a good number of situations like law enforcement encounters or trips to the emergency room for an extended hospital stay where your device can be physically accessed by other people.

Keeping more than a token, or useful but expendable amount of bitcoins on your mobile device responsibly means doing quite a bit more than most android users to secure your phone. Oh, how I wish there were a decent Blackberry app for bitcoin. Most of the world has passed them over, but for the security conscious few things lock down as easily for the price as a cheap Blackberry curve.

Then of course backing up your mobile's keys in Armory (preferably separated from your main wallet) can keep your coins safe if your phone succumbs to a worst case scenario.

Bitcoins in a mobile wallet are analogous to cash in a physical wallet. You carry around enough with you for routine purchases but keep your life savings somewhere more secure.